How many four-digit even whole numbers exist?

The fourth digit must be even, and there are 5 even digits (0, 2, 4, 6, or 8). Thus, the number of 4-digit even numbers is 9 x 10 x 10 x 5 = 4500.

Step-by-step explanation:

I hope this helps

∠acb = 8°

step-by-step explanation:

∠xba lies on the circle and is half the measure of the intercepted arc ax

hence

measure of arc ax = 2 × 42° = 84°

∠acb is outside the circle and is

∠acb = (arcab - arcax ), hence

∠acb = 0.5 (100 - 84) = 0.5 × 16° = 8°

7/2

(decimal: 3.5)

welcome ; )

step-by-step explanation: