Can someone help me answer this

Find the value of the cosine for angle a

Brent needs to paint a logo made using two right triangles. the dimensions of the logo are shown below. what is the difference between the area of the large triangle and the area of the small triangle? (1 point) select one: a. 4.5 cm2 b. 8.5 cm2 c. 16.5 cm2 d. 33.0 cm2

The radius of the circle is 4 cm and the measure of the central angle is 90° the area of the sector with a central angle measuring 90° and radius of length 4 cm is vt cm the triangle in the sector is 4 cm the area of the triangle is v/cm² the area of the segment of the circle is (471 - ) cm?