Final answer:
Angle a cannot be determined from the given information.
Step-by-step explanation:
The measure of angle a can be found by using the trigonometric relationship between the sides of a right triangle. Given that y / 0 = 0.7, we can rewrite the expression as y = 0.7 * 0.
This means that either y or 0 must be equal to zero, which implies that the triangle is not a right triangle. In a right triangle, one of the angles must be 90 degrees.
Therefore, none of the provided answer choices (a, b, c, d) are correct for angle a.