summary stats<-data_clean %>%                                                                  group_by(Trench)%>% +                                                                     summarise(                                                                                Trench    n = n(),
L_mean = mean(Lmm, na.rm = TRUE),
L_sd = sd(Lmm, na.rm = TRUE),
B_mean = mean(Bmm, na.rm = TRUE),
B_sd = sd(Bmm, na.rm = TRUE),
T_mean = mean(Tmm, na.rm = TRUE),
T_sd = sd(Tmm, na.rm = TRUE),
W_mean = mean(Weightgm, na.rm = TRUE),
W_sd = sd(Weightgm, na.rm = TRUE)
) %>%
    arrange(desc(n))

unexpected symbol in "summary stats"

unable to correct??????????/

pl advise