What will happen when water and pebbles and pour it on the other cup?

The water level in the bucket would drop.

This is because the pebbles have a greater density than water - they displace more water (when floating in a cup), than their volume. Thus the water displaced by the cup of floating pebbles has to be more than the volume of pebbles in the cup.

spiders belong to a group of arachnids.

arachnids have the following traits :

they have two body parts.

they have eight legs unlike insects which have 6 legs.

they have no wings.

these traits distinguish them from insects.

the information that antonio is doubting us the statement that spiders differences are as a result of being first to evolve.

this is because the evolution of one species is independent of the other species.

measuring light intensity

light meters can be used to measure light intensity. the meter is held at the soil surface and pointed in the direction of the maximum light intensity, and then the meter is read.

errors can be made when measuring light intensity by accidentally shading the light meter. the reliability of the results can be checked by taking many samples.