Which expression is equivalent to 21 × 7?
A) 7 × 21
B) (3 x 7) + 7
C) (10 + 7) × 11
D) (21 + 7) × (7 + 21)

Which is a logical conclusion based on the given information? a. figure abcd is a rhombus by the definition of a rhombus. b. segment ac is congruent to segment dc by cpctc. c. angle acb is congruent to angle adc by the angle-side-angle theorem. d. triangle acd is congruent to triangle cab by the hypotenuse-leg theorem.