14 + 28 + 42 + 56 + … 280
= 14 (1 + 2 + 3 + 4 + … + 20)
= 14 × 20 × 21 / 2
= 2940
where we use the well-known identity,

$16.68 is the most expensive item you can order with $20.00
Answer:
thx for the 10 points
Step-by-step explanation:
Full cann = x actually go the link that person sent