quadratic function has an axis of symmetry of x = 3 and one x-intercept of (10, 0) , what is the other x-intercept?

If you flip a coin 3 times, what is the probability of flipping heads 3 times? a. p(3 heads) = 3/8 b. p(3 heads) = 1/6 c. p(3 heads) = 1/8 d. p(3 heads) = 1/2