Answer:
i think it would be B. Aluminum, Al and D. Boron, B
Explanation:
since they're both in group 13 and they forms a 3+ ion
An experimental design is used to assign variables for testing. In contrast to a control design where nothing is changed, the experimental design allows you to test various new inputs to see how they would vary from the original results.
Answer:
Earth's Tilt and The Seasons. Earth, like all of the planets in the Solar System, travels around the Sun. One complete orbit of the Sun is known as a year and it takes Earth 365 days, 5 hours, 48 minutes and 46 seconds to complete an orbit. The changing seasons are caused by the fact that Earth is tilted. please vote me brainliest i can't message no one cuz i haven't got enough points i'm desperate.
Explanation:
Explanation:
The machine whose efficiency is 100% is known as perfect machine .This machine is not possible in real life because every machine is affected by the overcoming friction due to which is efficiency become less than hundred percent .