36. For each line,as the concentration of salt in the nutris ent solutions increased.average plant mass: R increased only. decreased only. N increased, then decreased J. decreased then increased.

## Step 1<br />The problem is about the effect of increasing salt concentration in nutrient solutions on plant mass. The options provided are:<br />1. R increased only.<br />2. decreased only.<br />3. decreased.<br />4. decreased then increased.<br /><br />## Step 2<br />The correct answer is "decreased then increased" (Option J). This is because, in general, as the concentration of salt in the nutrient solution increases, the plant mass initially decreases due to osmotic stress. However, at a certain optimal concentration, the plant mass may start to increase again.<br /><br />## Step 3<br />This phenomenon is known as osmotic stress, where the high concentration of salt outside the plant cells causes water to move out of the cells, leading to a decrease in plant mass. However, at a certain optimal concentration, the plant may adapt and start to grow again, leading to an increase in plant mass.