1-A teacher started his class at 7:00 and 15 min and finished at 8:50 a. m. How many minutes did class last? 2-Doing physical exercises for 50 min per day for 20 days, how many hours will be spent per month to do these exercises?

3-In a school each class lasts 50 minutes and each class has 5 lessons per day. Knowing that there is a 30-minute break, calculate how many hours students spend per day at this school.

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(! ) what’s fracking and what does it have to do with carbon, carbon dioxide, or fossil fuels?

Which is an important function of normal flora? a. aid with bone marrow production. b. crowd out pathogenic bacteria. c. destroy digestive track pathogens. d. manufacture iron in the bloodstream.

(select all the correct choose each statement that is scientific. - the opinions of randomly selected participants in a survey prove the idea that global temperatures are not increasing on earth. - the universe's average temperature and rate of expansion support the idea that it began as one super-dense and hot mass 13.8 billion years ago. - ocean tides are caused by the uneven gravitational pulls of the moon and sun on different parts of earth. - human life is more valuable than other forms of life on earth because humans are more intelligent than other organisms.