Sonya buys four pairs of shoes on sale for buy one, get one 50% off. The sales tax is 6.5%. If the original price for each pair of shoes was $35, how much does Sonya pay for the four pairs altogether?

The first week samantha learned to read braille, she could read 10 words per minute. in the second week she increased her speed by 20%. in the third week she increased her speed again by another 25%. how many words could she read per minute by the third week? hurry and tell me!