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From the beginning of the day the temperature rose 15 degrees so that by 4 pm it was 87 degrees. what was the temperature at the start of the day

Glenda makes an online purchase for picture frames for $12.95 each and formats of $5.89 each the site says it taxes paid by the customer or 6.5% of the total purchase price shipping charges are based on the

Given sin28.4=.4756, cos28.4=.8796, and tan28.4=.5407 find the cos of 61.6