An insulated lunch bag keeps food warm by increasing the thermal energy of the lunch bag.
increasing the thermal energy of the food.
slowing the transfer of thermal energy from the air outside the bag to the food inside the bag.
slowing the transfer of thermal energy from the food inside the bag to the air outside the bag.

Although there are a limited number of amino acids many different types of proteins exist because..

Which statement about the immune system is false? a. lymphocytes reduce inflammation, b. b cells remember specific pathogens. c. most white blood cells kill bacteria d. white blood cells are made in lymph nodes.

Agroup of students is studying convection currents. they fill two identical balloons with the same amount of helium. one balloon is placed in a freezer and the other in an area with warm air. after 10 minutes, the balloons are released from a height of 1 meter. which of the following do the students most likely observe? question 8 options: the cold balloon expands and rises. the warm balloon shrinks and sinks. the balloons rise at the same rate. both balloons are the same size. the ballons both rise. the cold ballon is larger than the warm balloon. the warm balloon expands and rises. the cold balloon shrinks and sinks.