Equate what is inside cosine with
, base period and solve for x,



Hope this helps :)
Yay you’re not getting a profit because of how revenue works but I mean You made a basket
Kinetic Energy
=
1
2
m
v
2
=
1
2
1120
⋅
40
2
=
896000
J
=
8.96
⋅
10
5
J
U should use friendly numbers when subtracting.......the numbers have to be between 3 and 10