Will chose best answers and give maximum points please someone help me !!

List two coterminal angles with: -40º and 2π /3 radians

cos90sin30-sin^45+cos0

simplify cost/tant +sint

A wheel turn through 7.5 revolutions per second. How many radians per minute is this ?

1) coterminal just means the same place on a circle except rotated multiple times around it, or backwards around it.

-40 = 320 ; -400
2pi/3 = 8pi/3 ; -4pi/3


2) not sure what you want from this question but I'll assume a numerical answer
cos(90)*sin(30) -sin(45)+cos(0)
0*sin30 - 1/(sqrt(2)) +1

1-(1/sqrt(2))


3) tant=sint/cost
so
cost/(sint/cost) + sint
(cost)^2/sint + (sint)^2/sint
((cost)^2+(sint)^2)/sint
we know from Trig identity sint^2+cost^2=1

1/sint


4) 7.5 revs/sec. Convert revolutions to radians (1 rev=2pi radians) and seconds to minutes (60s=1min)
7.5*2pi=15pi radians /second *(60s/min)

900pi radians/sec


Hope this helps