May anyone help?? i didnt score correct also can someone please correct me

The graph shows the decibel measure for sounds depending on how many times as intense they are as the threshold of sound. noise in a quiet room is 500 times as intense as the threshold of sound. what is the decibel measurement for the quiet room? 20 decibels28 decibels200 decibels280 decibels

The half-life of a certain material is 0.004 second. approximately how much of a 20-gram sample will be left after 0.016 second? a. 5 grams b. 16 grams c. 0.32 gram d. 1.25 grams

The westins and the shermans live in the same city and pay the same sales tax rate, and both families made $14,000 in taxable purchases last year. if the westins made $86,000 and the shermans made $33,000 last year, is the sales tax in their city an example of a regressive tax? yes, because the westins and the shermans both paid the same sales tax rate. b. no, because the shermans paid a higher percentage of their income in sales tax than the westins did. c. no, because the westins and the shermans both paid the same sales tax rate. d. yes, because the shermans paid a higher percentage of their income in sales tax than the westins did.