Which expression is equivalent to 21 × 7?
a) 7 × 21
b) (3 x 7) + 7
c) (10 + 7) × 11
d) (21 + 7) × (7 + 21)

30 points

Lucy is a dress maker. she sews \dfrac47 7 4 of a dress in \dfrac34 4 3 hour. lucy sews at a constant rate. at this rate, how many dresses does lucy sew in one hour? include fractions of dresses if applicable

How do i start to solve? would appreciate a walk-thru! a bird sitting 16ft above the ground in an apple tree dislodges an apple. after how many seconds does the apple land on the ground? (assuming that no branches will interfere with it's fall)

Aconstruction worker has rope 9 m long he needs to cut it in pieces that are each 3 /5 m long how many such pieces can he cut without having any rope leftover?