Please help me with this biology question Chloroplasts are present in some plant cells only Give an example of plant cells that do not contain chloroplasts and explain why​

Exit what always affects measurement error in an experiment? a. investigator bias b. variability in nature c. instrument precision d. misreading the instrument

Arepair man charged $93.06 the price included 2 hours of labor and 40 service charge how much does the repairmen charge per hour for labor?

What sentence best supports the statement that hormones are involved in the regulation of homeostasis? a. the hormone erythropoeitin increases the production of red blood cells when oxygen levels are low. b. the hormone oxytocin promotes labor contractions of the uterus during childbirth. c. the hormone melatonin induces sleep and its production is slowed by exposure to light. d. the hormone cortisol suppresses the immune system and is produced when the body is under stress.