1) My brother was late ... shool yesterday. a)in b)for c)at 2) We couldn't do the...

Question

1) My brother was late ... shool yesterday.
a)in b)for c)at
2) We couldn't do the exercise. It was very ...
a) different b) favorite c) difficult

Answer 1

To be late for school — опаздывать в школу.
В №1 b.
В №2 c

Answer 2

В первом можно in, а можно at, если хочешь сказать, что он был в здании, то in,  а если не уточнено или около здания, то at,
2 - c