Can we substitute our judgment for that of the jury?

In a motion to appeal against a jury's finding that there was no substantial evidence to support the jury's verdict, does the appellate court have any power to substitute the findings of the jury? (California, United States of America)

Does a trial court's statement that it does not believe the jury is hopelessly deadlocked give the jury the impression the jury should convict defendant? (California, United States of America)

When a jury has been sworn in, can the trial court reopen jury selection after the jury has already been sworn? (California, United States of America)

Does the trial court's instructions to the jury that the jury must conclusively accept the previous jury's finding that defendant's guilt has already been decided? (California, United States of America)

Does a jury's finding on a felony-murder special-circumstance allegation based on erroneous instruction that a jury would not have convicted appellant of second degree murder if the jury had been given the same instruction? (California, United States of America)

When a jury asks a jury a question after retiring for deliberation, does the court have a duty to provide the jury with additional instructions? (California, United States of America)

Can a jury be found to have been prejudiced by a judge who made a nonstandard comment to the jury during jury selection? (California, United States of America)

Does a jury's misconduct in a jury trial prejudice a defendant who refused to take the witness stand because the jury did not want to hear from him? (California, United States of America)

Does a jury's misconduct in a jury trial prejudice a defendant who refused to take the witness stand because the jury did not want to hear from him? (California, United States of America)

Is there any case law where a prosecutor's argument that a jury would be "damaging" to the jury has been interpreted in the context of a jury trial? (California, United States of America)