it could
Any plant can pollinate with any plant. Just so long as there's bees there. Bees accidentally get pollen from other plants on there feet and can ACCIDENTALLY cross-pollinate. So, yes, a pear CAN pollinate with a plum tree.
Victoria plums are self fertile so do not require another plum tree to pollinate them.
Yes, plums need the correct pollinator. The right one depends on which variety you have.
You dig a hole and put the plum tree into it.
In a plum tree.
It may be aphids.https://www.gardeningknowhow.com/edible/fruits/plum/common-plum-tree-pests.htm
spraying a plum tree with what? against what pest/disease?
No.
Yes, but there is no guarantee tou will get a tree with worthwhile plums.
yes
No It's physicly impossible
no