In a presidential form of government, how is the head of the executive branch chosen

Dogs make wonderful pets because they us stay happy and healthy. the topic sentence is "dogs make wonderful pets." , is this correct? i keep doubting myself.

Aids is growing fastest in the poorest countries of africa. these nations don’t have enough doctors, medical labs, or money for medicine. a recent study showed that only a small percentage of hiv-infected children in africa are getting any medical treatment at all. what central idea is emphasized in both sources? the hiv/aids epidemic in africa is serious. the hiv/aids epidemic in south africa is serious. the hiv/aids epidemic among african children is serious. the hiv/aids epidemic among south african children is serious

Will give branliest and 25 points if answer all quesyions 1. select the correct prefix for the following base word: freeze (against freezing). a. im- b. inter- c. re- d. mis- e. anti- 2. select the correct prefix for the following base word: lock (lock between). a. im- b. inter- c. re- d. mis- e. anti- 3. select the correct prefix for the following base word: behave (behave badly). a. im- b. inter- c. re- d. mis- e. anti- 4. select the correct prefix for the following base word: mature (not mature). a. im- b. inter- c. re- d. mis- e. anti- 5.. select the correct prefix for the following base word: play (play again). a. im- b. inter- c. re- d. mis- e. anti-