4. Humans are using resources that they did 100 years ago. a. Fewer b. better C. more d. none natural

pls... po

Brianliest please! Spent a while on this.

Humans started using tools as cave men. 100 years ago, (just after the Victorian times to give you an idea), candles were used instead of lights. Horses and carriages were used rather than cars. Fires were lit in times for warmth, not radiators. After major discoveries such as electricity, inventions were bale to become far more exciting. We did not often use the old things that we used in the past as they might be less efficient, slower or more expensive. I would probably say that we use fewer resources from the past, and using improved versions of hose used in the past. Therefore either answer A or B. You might disagree with B because some inventions, electricity is again a good example, may be more useful and efficient however are contributing to climate change. This may change your view that modern resources are better than previous resources.

answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e