Answer:
shown in explanation
Step-by-step explanation:
a) ∆EPB similar to ∆ERG
b) angle BEP = angle GER (common angle shared)
angle EPB = angle ERG (corresponding angles, PB//RG, parallelogram)
therefore through Angle-Angle similarity test, ∆EPB is similar to ∆ERG
or explanation can also be shortened to
∆EPB is similar to ∆ERG (AA, similarity)
c) since proven they are similar ∆, then we can proceed to use property of ratio of corresponding sides being equal

RG = 200+300=500m

cross multiply (from what I've learnt)
2ep+700=5ep
ep= 700/3 = 233 ⅓m (answer for length EP)
Do the same for length BE(using ratio of corresponding sides)


cross multiply again to get:
5BE = 2BE + 800
BE = 800/3 = 266 ⅔ m (answer for length BE)