A desk was originally priced at $80 but went on sale for 50% off. If Kimi bought the desk and paid 5% sales tax, how much did she pay in total?

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!