Ceteris paribus, if a firm's tax rate is 30%, an decrease of $5000 in interest expense would result in a change in net income of $ and in a change in cash of $ a. up by $1500, down by $3500 b. up by $3500, down by $1500 c. up by $4000, up by $1000 d. down by $1500, up by $3500