In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

What was the church of San Tommaso  in Formis which has a mosaic medallion for?, Context: The last great period of Roman mosaic art was the 12th–13th century when Rome developed its own distinctive artistic style, free from the strict rules of eastern tradition and with a more realistic portrayal of figures in the space. Well-known works of this period are the floral mosaics of the Basilica di San Clemente, the façade of Santa Maria in Trastevere and San Paolo fuori le Mura. The beautiful apse mosaic of Santa Maria in Trastevere (1140) depicts Christ and Mary sitting next to each other on the heavenly throne, the first example of this iconographic scheme. A similar mosaic, the Coronation of the Virgin, decorates the apse of Santa Maria Maggiore. It is a work of Jacopo Torriti from 1295. The mosaics of Torriti and Jacopo da Camerino in the apse of San Giovanni in Laterano from 1288–94 were thoroughly restored in 1884. The apse mosaic of San Crisogono is attributed to Pietro Cavallini, the greatest Roman painter of the 13th century. Six scenes from the life of Mary in Santa Maria in Trastevere were also executed by Cavallini in 1290. These mosaics are praised for their realistic portrayal and attempts of perspective. There is an interesting mosaic medaillon from 1210 above the gate of the church of San Tommaso in Formis showing Christ enthroned between a white and a black slave. The church belonged to the Order of the Trinitarians which was devoted to ransoming Christian slaves.
ransoming Christian slaves

What is beneficial to London's economy?, Context: London is one of the leading tourist destinations in the world and in 2015 was ranked as the most visited city in the world with over 65 million visits. It is also the top city in the world by visitor cross-border spending, estimated at US$20.23 billion in 2015 Tourism is one of London's prime industries, employing the equivalent of 350,000 full-time workers in 2003, and the city accounts for 54% of all inbound visitor spend in UK. As of 2016 London is rated as the world top ranked city destination by TripAdvisor users.
Tourism

How do the trials occur?, Context: In the United States, new pharmaceutical products must be approved by the Food and Drug Administration (FDA) as being both safe and effective. This process generally involves submission of an Investigational New Drug filing with sufficient pre-clinical data to support proceeding with human trials. Following IND approval, three phases of progressively larger human clinical trials may be conducted. Phase I generally studies toxicity using healthy volunteers. Phase II can include pharmacokinetics and dosing in patients, and Phase III is a very large study of efficacy in the intended patient population. Following the successful completion of phase III testing, a New Drug Application is submitted to the FDA. The FDA review the data and if the product is seen as having a positive benefit-risk assessment, approval to market the product in the US is granted.

Following IND approval, three phases of progressively larger human clinical trials may be conducted