Given a math problem with context and a question and 5 answer choices, the task is to provide the correct answer choice based on the problem. You must choose one of the given answer choices by letter: a, b, c, d, or e; anything else is invalid.

Problem: a rope of which a calf is tied is increased from 12 m to 23 m, how much additional grassy ground shall it graze ?
Options: a. 2989, b. 2789, c. 1210, d. 1288, e. 1211
c

Problem: 6 / 9 of the population of the country of venezia lives in montague province, while the rest lives in capulet province. in the upcoming election, 80 % of montague residents support romeo, while 70 % of capulet residents support juliet; each resident of venezia supports exactly one of these two candidates. rounded if necessary to the nearest percent, the probability that a juliet supporter chosen at random resides in capulet is
Options: a. 64 %, b. 41 %, c. 45 %, d. 72 %, e. 78 %
a

Problem: a question paper has 2 parts, a & b, each containing 8 questions. if a student has to choose 8 from part a & 4 from part b, in how many ways can he choose the questions ?
Options: a. 110, b. 70, c. 120, d. 130, e. 140

b