Could you please confirm for me that the given answers to the following questions are incorrect, based on their given working? I strongly believe that they're wrong, but I want to be certain. c:

Q1. - Is the correct answer cotx?

Q2. If sinx = 2/√7 and cosx<0, find the exact value of tanx.

- Given working. Shouldn't it be -(2√3)/3?

Q3. From the top of a lighthouse 70m above sea level, the angles of depression of two buoys due north of the lighthouse are 60 deg. and 25 deg. respectively. Find the distance between the two buoys. (Answer in 2 dec. pl.)

- Shouldn't it be 109.70m (2 dec. pl.)?

Q4. Highlighted questions =>

Given working: - Shouldn't it be for (iii), BQ = htan79°, and for (iv), h = 108m (nearest m)?

Thanks in advance!

P.S. Please don't feel like you need to answer all the questions at once. Any help is help!