If the half-life of a sample of a radioactive substance is 30 seconds, how much would be left after 60 seconds? <span>
A. one-fourth</span>
Answer:
True
Explanation:
The first artificial use of a PGR was to stimulate the production of flowers on pineapple plants. They are now used widely in agriculture. Plant hormones are also used in turf management to reduce the need to mow, to suppress seedheads, and to suppress other types of grass.
The best answer among the choices given is option A. Chemical weathering of rocks is a source of dissolved substances in the ocean. It is a process that involves the erosion of rocks due to chemical reactions by water and substances dissolved in the water. Therefore, it most likely the source of dissolved substances.
Typical day of a new day in my house with my phone in my car so I’m not going hard I don’t know how much it was
An electron has a relative mass of 0, whilst an alpha particle has a relative mass of 4
An electron has a relative mass of 0, whilst a proton has a relative mass of 1
A neutron has a relative mass of 1, whilst an alpha particle has a relative mass of 4
A neutron has a relative mass of 1, and a proton also has a relative mass of 1
