Step-by-step explanation:
He can type 62 words a minute. But I don't know the speed. sorry:(
Answer:
8 min = 496 words
1 minute = 496/8
= 62 words
i think it's a. Not so sure though
9t²-16u² = 3²t²-4²u² = (3t)²-(4u)² = (3t+4u)(3t-4u)
30