Why do dogs wag their tail when you call them by their name?

What is the best approach to selecting safety equipment for an activity

Which barrier to economic development is shown in the following examples? i. the high rate of hiv infection in underdeveloped nations ii. the use of children as soldiers in uganda’s army in the early 2000s iii. low literacy rates in underdeveloped nations with limited exposure to adequate education a. foreign debt b. political instability c. widespread disease d. low levels of social welfare

Which of these are fast-acting compounds that attack ocygen-dependent tissues known to be particularly sensitive to these compounds? a. nerveb. vesicantsc. cyanide compoundsd. pulmonary