Hii... can someone please help me with my maths question

Find the value of cos x​

Abike shop sells you a bicycle for $63 and a helmet for $21. the total cost is 150% of what the shop spent originally. how much did the shop spend originally? how much profit did the bike shop earn by selling the bicycle and helmet to you ?

For each proportion find the unknown number x 1/5/8=×/15

Given: pqrs is a parallelogram prove: pr and qs bisect each other at t