Im very confused with how to solve and would like help please

Given: circle o, cd is diameter, chord ab || cd. arc ab = 74°, find arc ca.

Write the equations in logarithmic form 7^3=343

F. a fair coin is thrown in the air four times. if the coin lands with the head up on the first three tosses, what is the probability that the coin will land with the head up on the fourth toss? a. 0 b. 1/16 c. 1/8 d. 1/2