Read the following information carefully to answer the questions.
(i) ′P×Q′ means 'P is the wife of Q'.
(ii) ′P+Q′ means 'P is the father of Q'.
(iii) ′P+Q′ means 'P is the son of Q'.
(iv) ′P−Q′ means 'P is the sister of Q'.
In ′J−F+R×B′, how is R related to J?