Factor using the identity: a3 + b3 = (a + b)(a2 – ab + b2) z3 + 8 (z + 2)(z2 – 2z + 4)? (z + 2)3? (z3 + 8)(z2 – 8z3 + 64)? (z + 8)(z2 – 8z + 64)?

The first week samantha learned to read braille, she could read 10 words per minute. in the second week she increased her speed by 20%. in the third week she increased her speed again by another 25%. how many words could she read per minute by the third week? hurry and tell me!