Question: In what country is the grading system based on a 1/4 point scale and has five letter grades?

Context paragraphs:
Bloom–Richardson grading system: The Bloom–Richardson grading system from 1957 refers to a breast cancer classification system to grade breast cancers, and was the precursor of the present criteria, the modified Bloom–Richardson–Elston grading (BRE) system (also called the Nottingham system.)  The cells and tissue structure of the breast cancer are examined histopathologically to determine how aggressive the cancer is.  Lower grade tumors, with a good prognosis, can be treated less aggressively, and have a better survival rate.  Higher grade tumors are treated more aggressively, and their intrinsically worse survival rate may warrant the adverse effects of more aggressive medications.  The references highlight the historical and current criteria; the latter system is judged more reproducible and is the recommended grading method.  The breast cancer classification article has further details of current breast cancer grading criteria.

Academic grading in Canada: Academic grading in Canada varies by province, level of education (e.g., high school or university), institution (e.g., Queens), and faculty.  The following are commonly used conversions from percentage grades to letter grades, however, this is not necessarily meaningful, since there is not a uniform scheme for assigning percentage grades either.  A grade A would be 80–100% a B would be 70–79%.

ECTS grading scale: The ECTS grading scale is a grading system defined in the European Credit Transfer and Accumulation System (ECTS) framework by the European Commission.  Since many grading systems co-exist in Europe and, considering that interpretation of grades varies considerably from one country to another, if not from one institution to another, the ECTS grading scale has been developed to provide a common measure and facilitate the transfer of students and their grades between European higher education institutions, by allowing national and local grading systems to be interchangeable.  Grades are reported on a carefully calibrated and uniform A-to-F scale combined with keywords and short qualitative definitions.  Each institution makes its own decision on how to apply the ECTS grading scale to its system.

Contract grading: Contract grading is a form of grading which results from cooperation between an instructor and his or her student, and entails contracted number of assignments of specified quality that correspond to specific letter grades.  Contract grading may be contrasted with other grading methods, such as grading on a curve or percentile systems.

Academic grading in Iran: The Iranian grading system is similar to that of France's in secondary schools and universities; the passing grade is 10.  Graduate programs require 12 and 14 as passing grades for Master's and Ph.D. level programs, respectively.  Iranian grades are not convertible to the 4.0 scale GPA directly, and should be used according to the destination universities' regulations.  Usually a grade of more than 16/20 is considered excellent.  The following table is most commonly used by world institutions and universities to convert from the Iranian grading system:

Academic grading in Vietnam: The Vietnamese grading system is an academic grading system utilized in Vietnam.  It is based on a 1-10 point scale, similar to the US 1.0-4.0 scale.

Academic grading in Tunisia: The Tunisian grading system is mostly a over20point grading scale: it is used in secondary schools and universities.  For primary schools, a new system has been introduced, based on a letter-grade scale; the old system uses a 10-point grading scale for the first term and a 20-point scale for the second and third terms.

Academic grading in the United States: Academic grading in the United States commonly takes on the form of five letter grades. Traditionally, the grades are A, B, C, D, and F — A being the highest and F, short for "failed", the lowest.  Numeric to letter grade conversions generally vary from system to system and between academic disciplines.

Antioch University: Antioch University is a non-profit 501(c)(3) private university system in the United States with five campuses located in four states.  All campuses of the university are regionally-accredited by the Higher Learning Commission, one of the six regional accreditors.  Campuses are located in Los Angeles, California; Santa Barbara, California; Keene, New Hampshire; Yellow Springs, Ohio; and Seattle, Washington.  Antioch University uses the system of narrative evaluation as a substitute to the conventional grading system of A-F letter grades.  Additionally, Antioch University houses two institution-wide programs, the Ph.D. in Leadership and Change and Antioch Education Abroad.  While it originated from the historic college, Antioch University should not be confused with Antioch College in Yellow Springs, Ohio, which gained its independence from the University in 2009, and has since had no affiliation with the University.

Gao Bing: Gao Bing (高棅, 1350 to 1423) flourished during the newly established Ming Dynasty (1368–1644) as an author and poetry theorist.  Gao Bing collected and arranged Tang poetry-era poems and wrote commentary material upon them in a work published as the "Graded Compendium of Tang Poetry" ("Tangshi Pinhui", 唐詩品彙), a seminal work using prosodic principles in a systematic method to classify poetry by Classical Chinese poetry forms.  It contained 5,769 poems by 620 poets, along with notes and commentary.  The "Tangshi Pinhui" aimed in part to correct what Gao Bing saw as lacking in previous works, particularly those of Song critic Yan Yu and Yuan critic Yang Shihong ("fl" 1340).  Other works would later build upon the "Tangshi Pinhui" system which would later greatly influence the perception of Chinese poetry: in part because of Gao Bing's explicit nine-rank grading system (similar to the nine-rank grading system of the Imperial examination system), by which he evaluated the works of poets such as Du Fu, Li Bai, and Wang Wei.

Supporting paragraphs: Academic grading in Vietnam Academic grading in the United States
Answer: the United States