Nguyên tử của nguyên tố hóa học X có cấu hình electron lớp ngoài cùng là (n–1)d5 ns1 (n

4). X ở

Light waves travel than sound waves.

How can a give a full method for the experiment of separating sand from water by filtration? 1-materials 2-steps 3-conclusion also for water and salt separated by the evaporation or distillation process

Sum of brother and sisters age is 26. four times the brothers age is subtracted from three times the sisters age, the difference is 8. what are the ages of the brother and sister?