In Exercises 11 and 12, the matrices are all n × n. Each part of the exercises is an implication of the form “If ? statement 1?, then ? statement 2 ?.” Mark an implication as True if the truth of ? statement 2 ? always follows whenever ? statement 1 ? happens to be true. An implication is False if there is an instance in which ? statement 2 ? is false but ? statement 1 ? is true. Justify each answer.a. If there is an n × n matrix D such that AD = I , then DA = I.b. If the linear transformation x ? Ax maps ?n into ?n, then the row reduced echelon form of A is I .c. If the columns of A are linearly independent, then the columns of A span ?n.d. If the equation Ax = b has at least one solution for each b in ?n, then the transformation x ? Ax is not one-to-one.e. If there is a b in ?n such that the equation Ax = b is consistent, then the solution is unique.

Growth True growth Increase in weight due to protein and bone deposition and fat deposition which is part of the developmental process Does not include excess fat deposition Don't know Why growth starts How it is regulated Why it stops DNA is ultimate regulator Cell size and number are regulated to reach genetically determined value Growth occurs in 2 ways Hyperplasia Increase in cell numbers Occurs before birth Some exceptions Some adipose cells continue to divide and get new cells for a while after birth Skin Slough cells Repair wounds Intestinal lining