I need to figure out why I am getting these question wrong. I keep on messing up the formula. I need the formulas so that I can have them for the upcoming test next week, practice tests

Net sales total $803,000. Beginning and ending accounts receivable are $80,000 and $74,000, respectively. Calculate days' sales in receivables. (D A. 32 days 0 B. 41 days 0 C. 35 days 0 D. 34 days Kyler Shea Tennis Academy held investments in trading securities with a fair value of $40,000 at December 31, 2014. These investments cost Kyler Shea $33,000 on January 1, 2014. What is the appropriate amount for Kyler Shea to report for these investments on the December 31, 2014, balance sheet? O A. $33,000 (9 B. $7,000 gain 0 c. $40,000 0 D. cannot be determined from the data g'wen Neal Company had the following information in 2014. Accounts receivable 12/31/14 ................................ $ 9,000 Allowance for uncollectible account 12/31/14 (before adjustment) ...... 650 Credit sales during 2014 ............................... 46,000 Cash sales during 2014 .................................... 11,000 Collections from customers on account during 2014 ................ 48,000 If uncollectibie accounts are determined by the agingof-receivables method to be $1 ,280, the uncollectible account expense for 2014 would be $630. The balance of the Allowance account after the adjusting entry would be 0 A. $630. 0 B. $650. 0 c. $1,280. 0 D. $1.930. Cornelius Company had the following information in 2014. Accounts receivable 12/31/14 ................................ $ 11,000 Allowance for uncollectible account 12/31/14 (before adjustment) ...... 850 Credit sales during 2014 ............................... 39,000 Cash sales during 2014 .................................... 13,000 Collections from customers on account during 2014 ................ 46,000 Uncollectible accounts are determined by the percent-of-sales method to be 4% of credit sales. How much is uncollectible-account expense for 2014? O A. $440 0 B. $550 c. $1,560 0 D. $2,080 Daniel Company had the following information in 2014. Accounts receivable 12l31/14 ................................ $ 14,000 Allowance for uncollectible account 12l31l14 (before adjustment) ...... 900 Credit sales during 2014 ............................... 47,000 Cash sales during 2014 .................................... 10,000 Collections from customers on account during 2014 ................ 47,000 If uncollectible accounts are determined by the aging-of-receivables method to be $1,030, the uncollectible-account expense for 2014 would be: 0 A. $130. 0 B. $900. 0 C. $1,030 0 D. $940